Starter for internal-combustion engines



y 5, 1947- D. 1.. MILLER STARTER FOR INTERNAL COMBUSTION ENGINES Filed July 7, 1945 I iv Patented May 6, 1947 STARTER FOR IN TERNAL-COMBUSTION ENGINES Donald L. Miller, Pine City,

N. Y., assignor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application July 7, 1945, Serial No. 603,716

6 Claims.

The present invention relates to a starter for internal combustion engines and more particularly to an engine starter of the outboard type in which a pinion is moved longitudinally away from the starting motor to engage and rotate an engine gear, which starter embodies a member of elastically deformable material such as rubber for a yielding element in the driving connection.

It is an object of the present invention to provide a novel engine starter drive of the outboard type incorporating a yielding member of rubber or the like.

It is a further object to provide such a device which is self-contained, strong, compact and substantially enclosed to protect the mechanism against the entrance of dirt, and other foreign matter. I

It is another object to provide such a device embodying a resilient member in the driving connection between a pinion controlling member and a pinion stop member.

It is another object to provide such a, device in which an abutment for limiting traversal of the starter pinion is located at the rear of the drive.

It is a further object to provide such a device including a traversing member for the pinion which is constructed as the drive enclosure and incorporates an abutment for positively limiting the traversal of the pinion,

It is a further object to provide such a device in which a single spring serves to ensure traversal of the pinion, and is also used as a mesh-enforcing spring for facilitating proper engagement of the pinion with an engine gear.

It is a further object to provide such a device having a housing for the resilient member, said housing having means thereon for traversing the pinion and further serving to arrest the traversing movement of the pinion.

It is a still further object to provide such a device wherein the driving stresses through the resilient member are closely coupled.

Further objects and advantages will be apparent to those skilled in the art by referring to the following description and accompanying drawing, in which:

Fig. 1 is a side elevation partly in section of the starter drive constituting a preferred embodiment of the invention. the parts being shown in idle position;

Fig. 2 is a view similar to Fig. 1 showing the drive in operating position;

Fig. 3 is a perspective. view of the pinion and barrel members in disassembled relation, the barrel being broken away to show its construction; and

Fig. 4 is a perspective view of the operating member for the drive.

form of an operating member are provided having an externally threaded sleeve 3 which is fixed on the power shaft by any suitable means;

such as a reduced portion I keyed to the shaft as indicated at 5, and anchored by a set screw 6. The exterior surface of the screw sleeve is provided for a. portion of its length with threads I which terminate at the rear end in an abrupt shoulder 8. The interior of the sleeve forms a recess 9 which terminates at the anchored end in a radial stop shoulder or abutment surface I I, and the open end of the sleeve provides a smooth radial abutment surface [2.

A control member in the form of a casing l3 substantially enclosing the starter drive is provided having interior threads M for engagement with the threads 1 on the screw sleeve. In order to permit the threads I and l to disengage or run off each other, the casing member I3 is counterbored at l5 for a portion of its length, thereby providing a clearance for the threads I.

An engine driving member in the form of a pinion I6 is slidably journalled on the shaft I for traversal into engagement with an engine gear I! to crank the engine. The pinion I6 is operatively connected to the casing l3 by a flange l8 fixedly mounted on the rear portion of the pinion and having lugs I9 on its periphery engaging within slots 2| of the casing l3 and held therein by a spring lock Wire 22.

Unitary means are provided for the dual functions of enforcing meshing of the pinion IS with the engine gear I! and facilitating the re-engagement of the threads 1 and I4 has run off the end of the threads. For this purpose, the slots 2| are elongated so as to permit the lugs l9 to have a limited amount of longitudinal travel therein and consequently allow the pinion 'l 6 to telescope within the casing. This relative movement of the pinion member is oppose by a compression spring 23 bearing at one end on the pinion flange i8 and at the other end on a disc 24 adapted to seat against a shoul der 25 in the casing IS. The spring 23 also after the casing I serves as a reentry spring for the threads I and I4 since, as shown in Fig. 1, when the parts are in idle position, the disc 24 bears on the front radial surface 26 of the screw sleeve 3 instead of the shoulder 25, thereby compressing the spring 23 by the final longitudinal movement of the casing as it runs oif the ends of the threads I. An abutment member 21 having an annular recess 28 is threaded in the rear end of casing 13 as indicated at 29 and has an inner axial extension 3| providing a radial abutment surface 32. The recess 28 is adapted to telescope over the open end of sleeve 3, and cooperates with the abutment surface l2 to positively stop longitudinal movement of the pinion.

Means are provided for yieldingly limiting the traversal of the casing and pinion in the form of a ring 34 of elastic material such as rubber seated in the recess 9 of the screw sleeve against the stop shoulder H and retained by a closure disc 35. The closure disc maintains the elastic ring 34 under a slight initial pressure by means of the lock wire 36 seated in a groove 31 in the interior of the screw sleeve 3, and is engaged by the abutment 32 when the pinion approaches its fully meshed position so as to provide a yielding stop therefor.

Means for opposing drifting of the pinion toward the flywheel are provided in the form of a compression spring 38 bearing at one end on the closure disc 35 and at the other end against the bottom 33 of the annular recess 28.

In operation, rotation of the power shaft i causes screw sleeve 3 to rotate and by reason of the expansive force of the spring 23 the threads 1 and [4 of the sleeve and casing l3 engage and traverse the casing to the right in Fig. 1. Pinion i6 is accordingly traversed into mesh with the engine gear I! until the abutment surface 32 of the member 21 engages the closure disc 35. Further longitudinal movement of the pinion causes the elastic ring 34 to be compressed until the resistance of the engine to rotation is overcome and the motor proceeds to crank the engine. Should the elastic member 34 become worn or wear should occur in other parts of the drive, a positive stop for preventing the casing from contacting the ring gear is provided by a continuance of the same meshing movement to the point where abutment surface 33 impinges upon the abutment surface I2 on screw sleeve 3.

It will be noted that during the meshing movement of the pinion, the clearance between the shoulder 25 and the disc 24 is first taken up and then the disc 24 bears only on the shoulder 25. Thereafter the spring 23 acts as a mesh-enforcing spring by yielding in case the teeth of the pinion IG lodge against the teeth of the engine gear I! during the'meshing movement, and throwing the pinion into initial mesh when sufficient torque is built up in the threads 1 and i4 to index the pinion teeth into registry with the tooth spaces of the flywheel.

It will-be seen that there is here provided a starting drive in which the operating member also incorporates a stop means for the traversal of the pinion and a housing for the elastic driving member and in which the operating parts of the drive are substantially enclosed and protected.

Although but one embodiment of the invention has been shown, and described in detail, it will be understood that other embodiments are possible and changes may be made in the proportions and arrangement of the parts without departing from the spirit of the invention as defined in the appended claims.

What is claimed is:

1. In an engine starter, a motor shaft, and a screw sleeve fixed thereon having a thrust shoulder, a casing member provided with threads fitting said screw sleeve, said interfitting threads being adapted to disengage when the starteris in idle position, a spring cooperating with said thrust shoulder and the casing member for assuring re-engagement of said threads when said sleeve rotat'es, a pinion slidably journalled on said shaft for rotation therewith and for movement thereby into meshing engagement with an engine gear and operatively connected to said casing member, means including said spring for enforcing mesh of the pinion with the engine gear, and means including an elastic member and abutments on said sleeve and casing foryieldingly arresting the meshing movement of the casing and pinion.

2. In an engine starter drive, a motor shaft, a sleeve fixed thereon having an interior recess and exterior threads, an enclosure member partially threaded on the interior surface thereof to form a disconnectable threaded connection with said sleeve, a pinion slidably journalled on said shaft and movable by the enclosure member to engage and rotate a gear of the engine to be started, unitary means between said enclosure member and pinion for reconnecting said sleeve thread and member provided with a helical connection to said operating member and having an abutment member fixed in the rear portion thereof, a pinion slidably journalled on said shaft for transversal into and out of mesh with a gear on the engine to be started, said pinion being non-rotatably connected to said casing but capable of limited yielding axial movement with respect thereto; and an elastic member housed in the-hollow portion of said operating member cooperating to provide a yielding driving connection between said operating member and easing member.

5. In an engine starter, a motor shaft, a screw sleeve fixed to said shaft and provided with an interior recess terminating in a radial surface, a ring of elastic material seated in said recess against said radial surface, a closure disc in said recess for maintaining said ring under initial compression, an enclosure casing having interior threads engaging said screw sleeve and a radial abutment surface in axial alignment with said closure disc, and a pinion slidably journalled on said motor shaft and operatively connected to the casing for transversal into meshing engagement with an engine gear.

6. In an engine starter, a motor shaft, a hollow 6 tion to said screw sleeve and threaded thereto, a pinion slldably journalled on said motor shaft for REFERENCES CITED transversalmto cranking engagement The following references are of record in the on the engine to be started and operatively confil of this patent: nected to said control member, a recessed member 5 in the rear end of said control member having an UNITED STATES PATENTS annular abutment surface thereon in axial align- Number Name Date ment with said closure disc, and means for oppos- 2,0 4, 3 Lansing June 22, 9 in; drifting of the pinion from idle position in- 2,1 5, 53 s u o 1933 eluding a spring seated in said recess and bearing 10 2,199,349 s u 30, 1940 a a st sa d di c. 2,356,984 Fitz Gerald Aug. 29. 1944' DONALD L. MILLER. 

